Lightweight bobbin



Feb. 13, 1968 F. T. NETTLES LIGHTWEIGHT BOBBIN Filed July 5, 1966 INVENTOR: I

BY I I %o usy United States Patent Oil ice 3,368,774 Patented Feb. 13, 1968 3,368,774 LIGHTWEIGHT BOBBIN Forrest T. Nettles, Charlotte, N.C., assignor to Celanese Corporation, New York, N.Y., a corporation of Delaware Filed July 5, 1966, Ser. No. 562,699 8 Claims. (Cl. 242--118.7)

ABSTRACT OF THE DISCLOSURE Lightweight bobbins and yarn wound structures employing such bobbins, the lightweight bobbin, which may be a flanged bobbin, employing a barrel of insuflicient thickness to retain dimensional stability under yarn winding tensions and rigid reinforcing members floatably secured to the outer face of the barrel.

This invention relates to lightweight bobbins and more specifically to lightweight bobbins having sufficient rigidity to prevent deformations from yarn winding tensions.

The vast majority of synthetic yarn winding bobbins presently in operation are heavyweight Wood or metal bobbins, the weight being due to the large diameters which are necessary in order to wind at the same speeds at which synthetic yarns are being formed. Efforts have been made to reduce the weight and consequently the cost of these heavyweight bobbins. Most of these efforts, however, have proven unsatisfactory due to a lack of dimensional stability in lightweight bobbins when subjected to yarn winding tensions. The principal weakness of lightweight bobbins which have heretofore been employed is a weakness in the central section of the bobbin, the weakness causing the middle portions of the bobbin to collapse as yarn is wound about it. The collapse of a central section of a bobbin would, of course, result in the bobbin locking itself to a spindle preventing release of a final yarn wound product. The collapsed central portion will also frequently trap yarn and render this yarn unusable. In addition to these aforementioned difl'lculties, the collapse of the central section of the bobbin would also deform the end flanges, with the result that the warped or deformed end flanges would trap yarn in the terminal portions of the bobbin and render this yarn unusable.

It should be understood that the term collapse as employed herein is meant to define caving or falling in as distinguished from a uniform compression such as is produced by controlled forces.

The phrase lightweight as employed herein is deemed to define a bobbin wall thickness or bobbin flange thickness which is insuflicient to retain dimensional stability under yarn winding tensions.

While deformation by collapse of lightweight bobbins is, of course, a serious disadvantage, the advantages inherent in lightweight bobbins are readily apparent. A lightweight bobbin, because of its low cost, may be used as a sales package thereby allowing a yarn manufacturer to bypass an expensive rewinding operation. The lightweight bobbin also results in an overall reduction in weight in the yarn wound package, thereby minimizing the work involved in multiple handling operations of yarn wound packages.

It is, therefore, an object of this invention to provide a lightweight bobbin which will not collapse in yarn winding operations.

It is another object of this invention to provide a lightweight flanged bobbin which will not collapse and will not deform flanges in yarn winding operations.

It is still another object of this invention to provide a lightweight flanged plastic bobbin which will neither collapse nor deform and which is readily disengaged from the driving spindle.

It is a further object of this invention to provide a yarn wound package employing a lightweight bobbin which will not collapse in yarn winding operations.

In accordance with this invention, it has now been discovered that a lightweight bobbin having dimensional stability may be achieved by mounting a plurality of longitudinally aligned reinforcing rib members around the exterior of the bobbin. The reinforcing rib members are preferably U-shaped members in order to reinforce the flanged sections of the bobbin and are also preferably mounted in a floating fashion.

While the exact dimensions of the bobbin is not critical to this invention, it should be noted that conventional synthetic yarn winding bobbins have a barrel wall thickness which is considerably in excess of the diameter of the bobbin drive spindle orifice. The lightweight bobbin of this invention, however, has a barrel wall thickness which is considerably smaller than the diameter of the bobbin drive and support orifice.

A better understanding of the invention may be had from a description of the drawings wherein:

FIGURE 1 is a partially exploded isometric view of a flanged reinforced lightweight bobbin of this invention;

FIGURE 2 is a cross sectional view taken along the line 2, 2 of the bobbin of FIGURE 1;

FIGURE 3 is a cross sectional view taken along the line 3, 3 of the bobbin of FIGURE 2;

FIGURE 4 is an isometric view of the mounted yarn wound bobbin of this invention;

FIGURE 5 is a cross sectional view taken along the line 5, 5 of the mounted yarn wound bobbin of this invention.

Turning to FIGURE 1 of the drawings, an isometric view of the lightweight bobbin of this invention is shown wherein a barrel member 1, having flanged portions 2 disposed at either extremity of barrel member 1, has U- shaped reinforcing members 3 secured thereto by means of button members 4 disposed on the interior face of reinforcing member 3. Button members 4 engage slots 6 disposed in flange members 2 and slots 6 disposed in barrel member 1. Button members 4 have, of course, a diameter which is greater than the short axis of slots 6. The buttons preferably have beveled edges in order to promote the insertion into the slot members. Slots 6 are elongated in order to provide a floating mount for U-shaped reinforcing members 3. Preferably both barrel member 1 and flange members 2 have a channel 7 disposed therein in order to seat U-shaped reinforcing members 3 in the manner such as to prevent U-shaped reinforcing member 3 from breaking the uniform contour of barrel member 1 and flange member 2. Channel member 7 extends continuously from one flange member 2 across barrel member 1 and into the opposite flange member 2. As can be seen in FIGURE 2 of the drawing, it is also preferred that the interior surface of barrel member 1 contain recessed areas 8 around slot members 6 in order that button members 4 will not project beyond the inner face of barrel member 1.

U-shaned reinforcing members 3 are preferably made from a high strength non-corrosive metal, such as for instance stainless steel. While button members 4 may be made of the same material as the reinforcing member, it is preferred that button members 4 be made of a flexible plastic such as for instance, polyethylene, polypropylene and fluorinated polypropylene. The use of such synthetic polymeric plastic button members is necessary where a rigid plastic material such as phenol formaldehyde resin is used in molding barrel member 1 and flange members 2. Where, however, barrel member 1 and flange members 2 are prepared from flexible polymeric materials such as, for instance, polyethylene, polypropylene or fluorinated polypropylene, button members 4 may be of the aforementioned metallic component which is similar to the body of U-shaped reinforcing member 3.

A better understanding of the desirability for cutting channel members 7 in the exterior face of flange members 2 and barrel member 1 and the interior face of barrel member 1 may be had from a discussion of FIGURE 3 of the drawings. In FIGURE 3 it may be seen that U-shaped reinforcing member 3 is positioned within channel member 7 so as to provide a common plane between the surface of flange member 2 and the surface of reinforcing member 3 which is disposed within barrel member 1 resides within channel member 7 in a manner such that the lands formed on barrel member 1 by channel members 7 have a radius which is common to that radius which is formed by reinforcing member 3. While it is not essential to the proper functioning of the lightweight bobbin of this invention, it is preferred that those portions of U-shaped member 3 which are in contact with barrel member 1 be given a slight curvature so as to coincide with the curvature of barrel member 1. In viewing the inner face of barrel member 1, it may be seen that channel members 8 disposed on the inner face prevent button members 4 from projecting beyond the surface formed by the inner face of barrel member 1. It will be appreciated that a smooth inner surface is essential on a bobbin in order that the bobbin member may be easily dofled and donned.

As previously mentioned, the function of the reinforcing members in the lightweight bobbin of this invention is to prevent the central section of the barrel member from collapsing and thereby pinching the yarn wound layers in the central sections of the bobbin and also to prevent flange members from buckling and pinching yarn wound layers at either extremity of the bobbin. While the discussion of the drawings have specifically dealt with flange bobbin members, it should be understood that a lightweight bobbin of this invention also has utility in the absence of flange members; that is to say, straight reinforcing members may be disposed on the exterior face of a lightweight sleeve member in order to produce a lightweight yarn winding sleeve.

It will be appreciated that the lightweight structure of the bobbin disclosed herein is such that yarn winding tension will cause the reinforcing members to float inwardly and the barrel portion to compress to a certain extent and lock itself to whatever support member or driving member the lightweight bobbin is disposed on. For this reason, it is necessary that the lightweight bobbin of this invention be disposed on a supporting means from which the bobbin in its yarn wound stage may be easily disengaged. Supporting means of this type are collapsible drum members, collapsible spindles and collapsible bobbin arbors. Due to the support which a collapsible drum furnishes throughout the interior surface of the lightweight yarn winding bobbin, the collapsible drum is preferred.

Turning to FIGURES 4' and of the drawings, an isometric view and a cross section thereof of one form of an extensible and contractible drum suitable for use in conjunction with this invention is seen. It should be understood that the degree of extensibility illustrated herein is not a limiting feature of the invention and that collapsible and extensible support means having varying degrees of flexibility may be employed. For ease of illu tration, the drive means for the extensible drum has not been shown. The drum may, however, be conveniently attached to the driving spindle of such well known textile apparatus or for instance a ring and follower downtwister. The drum must, of course, be properly balanced with suitable counter weights. The extensible and collapsible drum member 11 is shown supporting a yarn wound lightweight bobbin 12. Lightweight yarn wound bobbin 12 is secured to extensible and contractible drum member 11 4 by means of segment 13 which is shown in phantom view in FIGURE 4 and in cross section in FIGURE 5. Segment member 13 is forced outwardly, that it to say, into the drums extensible position by means of rotating shaft member 14 in a counterclockwise direction, the rotation forcing a shoulder of shaft member 14 against segment member 13 whereby segment member 13 is forced outwardly on pivot member 15. The drum is secured in this expanded position by means of ratchet member 16, the teeth of which are engaged by pawl member 17. It should be understood that after the yarn winding process is initiated upon the lightweight bobbin secured to the extensible and contractible drum that the yarn tensions cause a compression of the barrel on the lightweight bobbin and lock the yarn wound bobbin to the support member. Upon completion of yarn winding operations, it is of course necessary to free the yarn wound bobbin from the support member. The release of the yarn wound bobbin may be conveniently achieved with an extensible and contractible drum by releasing ratchet member 16 from pawl 17 and allowing shaft member 14 to rotate in a clockwise direction thereby releasing the pressure from the shoulder of shaft member 14 upon segment member 13 and allowing segment member 13 to drop down on pivot 15. This operation releases the yarn wound bobbin from the extensible and contractible drum support member. The lightweight bobbin of this invention when fully wound with yarn forms a rigid package and as such may be used as a sales package due to the low cost of the lightweight bobbin or may be used for subsequent textile processing operations.

Having thus disclosed the invention, what is claimed is:

1. A lightweight bobbin comprising a barrel of insufficient thickness to retain dimensional stability under yarn winding tensions, said barrel having channel members carrying slot members disposed in the outer face thereof extending along the longitudinal axis of the bobbin and rigid reinforcing members floatably secured within said channels by means of button members disposed on said reinforcing members and projecting through said slot members.

2. The lightweight bobbin of claim 1 wherein flange members are disposed at the terminal portion of said barrel and wherein said reinforcing members are U-shaped members extending from said barrel along each of said flange members.

3. The lightweight bobbin of claim 1 wherein recessed areas are disposed on the inner face of said barrel around said slot members whereby said button members will not project beyond said inner face.

4. The lightweight bobbin of claim 1 wherein said button members are flexible polymeric resin plastic buttons.

5. The lightweight bobbin of claim 1 wherein said rigid reinforcing members have a widthwise radius of curvature which is substantially equal to the radius of curvature of said barrel.

6. The lightweight bobbin of claim 1 wherein said barrel is a unitary molding having flanged members disposed at the terminal portions thereof.

7. A yarn wound package, said wound yarn being disposed on a lightweight bobbin comprising a barrel of insufficient thickness to retain dimensional stability under yarn winding tensions, said barrel having channel members carrying slot members disposed in the outer face thereof, extending along the longitudinal axis of the bobbin and rigid reinforcing members floatably secured within said channels by means of button members disposed on said reinforcing members and projecting through said slot members.

8. The yarn wound package of claim 7 wherein flange members are disposed at the terminal portion of said barrel and wherein said reinforcing members are U-shaped members extending from said barrel along each of said flange members.

(References on following page) 5 References Cited UNITED STATES PATENTS 6 FOREIGN PATENTS 356,409 7/ 1922 Germany. 288,397 4/ 1928 Great Britain. 584,474 1/ 1947 Great Britain.

GEORGE F. MAUTZ, Primary Examiner. 

